Tim Peake facing months of recovery following six month space mission

Astronaut Tim Peake will come down to Earth with a bump next week when he ends his six month mission aboard the International Space Station.Although floating in micro-gravity for half a year may appear harmless or even restful, in fact, the rigors of spaceflight leave a lasting mark on health.To begin with, Major Peake is likely to suffer Entry Motion Sickness (EMS) as he plummets back to his home planet next Saturday, with symptoms including headache, pallor sweating, dizziness, nausea and vomiting.

Tim Peake will return to the Baikonur Cosmodrome in Kazakhstan, where he said goodbye to his children in December

Once back on Earth the situation does not improve as Major Peake’s body readjusts to the crushing force of normal gravity. Although the ISS has around 90 per cent of the gravity of Earth, astronauts experience weightlessness because the space station is in continual free-fall as it orbits the planet.The period of getting used to feeling of Earth’s gravity is known as ‘readaptation’ and it can take anything between six weeks and three years for the body to return to pre-flight normality.To start with, in space the brain gets used receiving little data from the vestibular system, which controls motion, equilibrium, orientation and gravity.After landing at Baikonur Cosmodrome in Kazakhstan, Major Peake’s sensors will go into overdrive which can result in dizziness and vertigo as the brain tries to relearn the difference between up and down.

Tim Peake will return to the Baikonur Cosmodrome in Kazakhstan, where he said goodbye to his children in December

Read More::Scientists Warn: Humans may need fake gravity to reach Mars without brain damageThe lips and tongue have also become used to speaking in weightlessness so astronauts often struggle to speak when they land.Dr Dorit Donoviel, head of the National Space Biomedical Research Institute said: “On Earth, a complex, integrated set of neural circuits allows humans to maintain balance, stabilise vision and understand body orientation in terms of location and direction.“In space, this pattern of information is changed. The inner ear, which is sensitive to gravity, no longer functions as designed. On return to Earth, they must readjust to Earth’s gravity and can experience problems standing up, stabilizing their gaze, walking and turning.”One of the first sensations reported by astronauts when they land is a strong sensation of heaviness in the limbs as fluids begin to flow from the head and upper body back to the lower body.While in space, the heart has become smaller and blood volume has decreased. Because there is less blood volume, this results in a shortage of blood to the head and upper body.

Blood rushes to the head in space and astronauts often look puffy in the face CREDIT: ESA/TIM PEAKE

About 80 per cent of astronauts experience low blood pressure upon return which hinders their ability to do everyday things, like walking or driving a car, and some astronauts faint after space flights and most need to be stretchered away from their landing vehicle. For that reason astronauts are banned from driving for 21 days after landing.

Astronauts can also experience heart and blood vessel problems down the line, such as artery stiffness.As if that were not enough, astronauts lose up to 1.5 per cent of their bone mass for each month spent in space so Major Peake could be missing nearly 10 per cent by the time he touches down.The greatest loss is in the thighs and pelvis which can take 12 months to recover for six month spaceflight. Astronauts are at far greater risk of broken bones in their first year back on Earth and they can also lose up to 40 per cent of their muscle mass which requires lengthy rehabilitation.To put it in perspective, postmenopausal women who are untreated for bone loss lose the same amount of bone loss in a year as astronauts lose in a month.Tim Peak: Down to Earth

Major Peake ran a marathon in space but his muscles and bones will still have wasted despite two hours of training a day.Muscles are usually back to normal within six weeks but astronauts are not allowed to drive for 21 days after landing because of their weakness.There is also a high chance that Major Peake will require glasses or contact lenses when he lands. A study by Nasa found that near and distance vision became worse for 48 per cent of astronauts who had brief missions. It is thought that pressure on the optic nerve owing to microgravity is to blame. Many astronauts find their vision eventually gets better but some are left with permanent blurred vision.Major Peake told a press conference this week that he was most looking forward to the rain splashing on his face."This is going to sound truly remarkable but I most miss the rain," he told journalists. "Perhaps that's because I haven't had a shower for six months. The feeling of nice cold drizzle on my face right now actually sounds blissful."However rain could feel painful when he first returns to Earth. Astronauts also lose more skin cells during spaceflight and their skin softens on their hands and soles of their feet. Nasa’s Scott Kelly, who recently completed a year-long space mission complained that his skin felt ultra-sensitive after landing.

Tim Peake became the first Briton to spacewalkCREDIT: ESA

There is also a concern that space radiation may affect endothelial cells, which line the blood vessels, and could initiate or accelerate coronary heart disease. More than half of astronauts also show significant signs of immune dysfunction after long missions.But on the up side, astronauts tend to get taller in space because the discs of the spinal column have not been compressed by Earth’s gravity and so can lengthen. Kelly grew two inches during his year in space.The health issues are causing concern for scientists who are planning longer missions, particularly lengthy voyages to Mars.Dr Donoviel added: “I worry about the long term effects of space radiation. Radiation exposure will be during travel to and from Mars, currently estimated to be 6-7 months each way.“My next concern would be the Visual Impairment syndrome which may be due to increased pressure on the brain. If untreated, this could cause optic nerve damage and loss in peripheral vision.“And I worry about the consequences on mental health from the isolation – depression which would cause a crew member not to exercise, eat, and take care of his or herself.”

Profile | Tim Peake

Born:April 7, 1972 in Chichester, SussexEducation:Sandhurst military academy; Graduate of the Empire Test Pilot School; BSc (Hons) in Flight Dynamics and Evaluation from the University of PortsmouthMarried: Yes, with two sonsInterests:Skiing, scuba diving, cross country running and readingCareer Peake served for 18 years in the British Army including terms in Bosnia, Northern Ireland and Afghanistan, before beating more than 8,000 other hopefuls to be accepted into the European Space Agency.1994:Gained his wings after completing the army pilots' course1998: Became a qualified flight instructor2002:Starting instructing trainees in flying Apache helicopters2009:Retired from the army and became a senior helicopter test pilot2009:Joined the European Space Agency after being selected as an astronaut2010-12:Completed extensive training with ESA2013:Selected for a mission to the International Space Station2015:Begins his Principia mission after successful lift-off in Soyuz rocket